Sometimes a process may only take a few seconds. In these cases it's not worth showing a full progress bar, however it may be worth adding some form of a "loading" indicator.

有时候处理过程仅需短短几秒，这种情况下无需显示完整的进度，仅仅加入一个“载入”标示就好。

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During the installation, a task bar is displayed showing the progress of the installation.

在安装期间，会显示一个任务条，它显示安装的进度。

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Showing a real progress bar when uploading large files is an often requested (and quite informative) feature, which is not easily doable with the way the upload handling works in PHP.

在上传一个大文件时显示一个真正的进度条是经常需要的（并且非常友好的）功能，但在PHP的文件上传处理中这并不容易做到。

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Can you imagine installing a large software application on your computer without seeing a progress bar showing you its completion percentage?

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